3. Why PHP
Open Source
Very good support
C/Java like language
Cross Platform (Windows, Linux, Unix)
Powerful, robust and scalable
4. PHP Elements
Variables: placeholders for unknown or changing
values
Arrays: a variable to hold multiple values
Conditional Statements: decision making
Loops: perform repetitive task
Functions: perform preset task or sub task
5. PHP statements
<?php
your statement is here;
don„t forget to end each statement with semicolon
(“;”);
anything within this scope must be recognized by
php or you‟ll get error;
?>
6. Naming variables
Start with dollar sign ($)
First character after $ cannot be number
No spaces or punctuation
Variable names are case-sensitive
You‟re free to choose your own but …
… meaningful naming is much better.
7. Assigning values to variables
$myVar = $value;
$myVar = 3.4; # assign a number
$myVar = “I‟m cute”; // Assign a string
$myVar = $yourVar; /* assign a variable */
$myVar = “$name is a terrible creature”;
8. PHP Output & comments
echo:
echo “you‟re a creature”; // print you‟re a creature
echo $name; /* print value of variable $name */
echo(“my creatures”); # print my creatures
print:
print “you‟re a creature”;
print $name;
print(“my creatures”);
Also printf and sprintf
12. Making decision (if, if else, elseif)
if(condition is true) {
//code will be executed here
}
if(condition is true) {
//code will be executed here
}
else {
//code will be executed if condition is false
}
if(condition 1) { }
elseif (condition 2) { }
else { }
13. Comparison operator
Symbol Name
== Equality
!= Inequality
<> Inequality
=== Identical
!== Not identical
> Greater than
>= Greater/equal than
< Less than
<= Less or equal than
14. Logical Operators
Symbol Name Use
&& Logical AND True if both operands are true
and Logical AND Same as &&
|| Logical OR True if not both operands are
false
or Logical OR Same as ||
xor Exclusive OR True if one of operands is true
! NOT Test for false
16. Conditional (ternary) operator
condition ? value if true : value if false;
$age = 17;
$fareType = $age > 16 ? 'adult' : 'child';
17. Loop
while(condition is true) { statement; }
do { statement; } while (condition is true);
for(initial value; test; increase/decrease)
{statement;}
foreach(array_name as temporary variable) {
statement;}
18. Breaking loop
break: exit loop;
continue: exit current loop but continue next
counter
19. PHP Function
A block of code that performs specific task
represented by a name and can be called
repeatedly.
function function_name()
{
//code is here
return var; // may return value
}
20. Date & Time
time(): timestamp from 1st January 1970
date(format, timestamp):
Format:-
d: day of the month (1-31)
m: month (1-12)
Y: year in 4 digits
Timestamp (optional)
Default is current date and time
Date Add / Date Diff
Under DateTime class: DateTime:add, DateTime:diff
21. String function
strlen(str): string length
strpos(str, str_find, start): find string occurance
strrev(str): string reverse
substr(str, start_str, length): return part of string
substr_replace(str, replacement, start, length):
replace part of string
23. Building Form & input
<form action=“” method=“URL” enctype=“data">
</form>
method: get or post
action: URL to be accessed when form is submitted
enctype: type of data to be submit to the server
All inputs must be within the form
Textfield = <input type=“text” name=“”>
Checkbox = <input type=“checkbox” name=“”>
Radio Button = <input type=“radio” name=“”>
Textarea = <textarea name=“”></textarea>
List = <select name=“”><option
value=“”></option></select>
24. Getting information from form
print_r($_POST): form data retrieval in array
$_POST: contains value sent through post
method
$_GET: contains value sent through get method
25. MySQL function (connection)
Connection to database
mysql_connect(servername, username,
password)
<?php
$test = mysql_connect(“localhost”, “admin”, “pass”);
if($test)
echo “success”;
else
die(“cannot connect maa…”);
?>
Close connection using
mysql_close(connection_name)
26. MySQL (query)
Select database: mysql_select_db(“database”,
connection);
Run query: mysql_query(“SQL query);
<?php
$test = mysql_connect(“localhost”, “root”,””);
mysql_select_db(“data”, $test);
mysql_query(“Select * from table”);
?>
SQL query: SELECT fieldname FROM tablename
27. MySQL (Display query)
mysql_fetch_array($result)
$result is array of data
Example:
<?php
$result = mysql_query(“MySQL select
query”);
while($row = mysql_fetch_array($result)) {
echo $row[„fieldname‟];
}
?>
28. MySQL insert data
SQL command: INSERT INTO table_name
(field1, field2, …) VALUES (value1, value2, …)
Example:
mysql_query("INSERT INTO Address (No, Road,
Postcode) VALUES (11, „Jalan 19/2C', 40000)");
29. MySQL update data
SQL command: UPDATE table_name SET
field1=value1, field2=value2,... WHERE
field=some_value
Example:
mysql_query(“UPDATE Address SET
Postcode=40900 WHERE No=13");
30. MySQL delete data
SQL command: DELETE FROM table_name
WHERE some_column = some_value
Example:
mysql_query(“DELETE from Address WHERE
Postcode=40900");
